It sounds like right now you are running a 5.1 speaker set up - front left, center, front right, surround left, surround right, and a subwoofer. (The subwoofer is the .1 in the 5.1 setup). Your Onkyo receiver can power 7 speakers and run 2 subwoofers, so it is described as a 7.2 receiver. These Klipsch speakers are powered, so they are not what you need to take your system from 5.1 to 7.1. Your receiver can already power 7 speakers. Passive speakers (not powered) are more appropriate for your arrangement. The manual for your receiver gives examples of how to hook up the speakers and where to place them. Hope this helps.
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